The invention relates to the field of input devices suitable for operating display devices and other electronic devices. Many consumer electronics devices, such as televisions, video playback and recording devices, and cable boxes, have numerous complicated and esoteric functions that need to be controlled by a user from a distance. Some manufacturers provide users with complicated remote controls that include dedicated buttons for all of the device's functions. However, complicated remote controls are expensive and discourage casual users from operating the equipment.
As an alternative, the user interfaces for many consumer electronic devices employ on-screen displays to enable users to control many device functions. The on-screen display provides users with a graphical user interface. One type of graphical user interface is a menu-based user interface. Menu-based interfaces group functions together under one or more nested menus. User can move between menus using a joystick or directional pad included in the remote control. However, because menu-based interfaces often bury functions under one or more menus or sub-menus, they are often difficult to use. Additionally, users must often input numerous button presses to navigate to and select the desired menu item.
Pointer-based graphical user interfaces are widely employed to operate computers. Typically, users manipulate an on-screen pointer using a mouse to interact with the graphical user interface. Pointer-based graphical user interfaces allow users to view and manipulate icons for a large number of functions with relative ease. A mouse typically requires a flat, smooth surface to operate correctly. In office environments, where users are typically seated at a desk, a mouse is an effective input device.
However, in many applications, the user does not have access to a flat surface. In these applications, a mouse is difficult and inconvenient to use. In an example, a user standing and giving a presentation must often return to a podium, table, or other flat surface to manipulate a mouse. In another example, in home entertainment environment, a user is often seated or lying down on a sofa or reclining chair. In this environment, the user would often have to change position to operate a mouse. As a result of this disruption, mice are not widely used in casual environments where the user is not likely to be seated in front of a flat surface.
To implement a pointer-based user interface in consumer electronics devices, some remote controls for consumer electronics devices include a digital or analog joystick to control an on-screen pointer of a pointer-based on-screen display. Unfortunately, users often find controlling a pointer using a joystick to be difficult, non-intuitive, and frustrating.
Other types of input devices have been developed to provide users with more intuitive ways of directing an on-screen pointer. One of these types of devices is the light gun or light pen. Light guns and light pens typically determine a pointer location by measuring the timing of a raster-scan based display. As a result, these types of devices cannot operate from non-raster scanned displays, such as LCD, plasma, and non-CRT based projection displays. Another type of light gun projects a narrow infrared beam at a target point. A camera located behind the user detects beam and deduces the position of the target point. This type of light gun is complicated and expensive, requiring the installation of a camera on the opposite wall from the target display.
Another type of remote input device is the Gyromouse, made by Gyration Inc. The Gyromouse includes one or more solid-state gyroscopes adapted to sense movement. As the user manipulates this device, the gyroscopes detect the motion and send a signal, often via radio waves, to a receiver unit. The receiver unit then interprets this signal into a pointer movement. The disadvantages of this device are its complexity, cost, size, and power consumption. Moreover, this type of device is often only sensitive to large amounts of motion. Thus, users must move the device substantially to operate the pointer.
It is therefore desirable for input device to provide users with an intuitive pointing capability. It is further desirable that the input device be capable of operating in free space, rather than requiring a flat surface. It is also desirable for the input device to be inexpensive to manufacture, provide long battery life, and to work with a variety of different types of displays. It is additionally desirable for the input device to be easily integrated with a variety of devices, including consumer electronic devices such a televisions, DVD players and recorders, digital or personal video recorders, cable and satellite set-top boxes, and video game consoles.